From 6adb7e35ab9a09a60f7088c757d30502c5a7b19a Mon Sep 17 00:00:00 2001
From: Ted Kremenek <kremenek@apple.com>
Date: Mon, 26 Jul 2010 19:45:42 +0000
Subject: [PATCH] Consolidate #args checking for scanf/printf format strings.

llvm-svn: 109427
---
 clang/lib/Sema/SemaChecking.cpp | 61 +++++++++++++++++----------------
 1 file changed, 31 insertions(+), 30 deletions(-)

diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index cf22fcf58364..03ca084dd897 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -1169,6 +1169,11 @@ protected:
   SourceLocation getLocationOfByte(const char *x);
 
   const Expr *getDataArg(unsigned i) const;
+  
+  bool CheckNumArgs(const analyze_format_string::FormatSpecifier &FS,
+                    const analyze_format_string::ConversionSpecifier &CS,
+                    const char *startSpecifier, unsigned specifierLen,
+                    unsigned argIndex);
 };
 }
 
@@ -1270,6 +1275,30 @@ CheckFormatHandler::HandleInvalidConversionSpecifier(unsigned argIndex,
   return keepGoing;
 }
 
+bool
+CheckFormatHandler::CheckNumArgs(
+  const analyze_format_string::FormatSpecifier &FS,
+  const analyze_format_string::ConversionSpecifier &CS,
+  const char *startSpecifier, unsigned specifierLen, unsigned argIndex) {
+
+  if (argIndex >= NumDataArgs) {
+    if (FS.usesPositionalArg())  {
+      S.Diag(getLocationOfByte(CS.getStart()),
+             diag::warn_printf_positional_arg_exceeds_data_args)
+      << (argIndex+1) << NumDataArgs
+      << getSpecifierRange(startSpecifier, specifierLen);
+    }
+    else {
+      S.Diag(getLocationOfByte(CS.getStart()),
+             diag::warn_printf_insufficient_data_args)
+      << getSpecifierRange(startSpecifier, specifierLen);
+    }
+    
+    return false;
+  }
+  return true;
+}
+
 //===--- CHECK: Printf format string checking ------------------------------===//
 
 namespace {
@@ -1538,22 +1567,8 @@ CheckPrintfHandler::HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier
   if (HasVAListArg)
     return true;
 
-  if (argIndex >= NumDataArgs) {
-    if (FS.usesPositionalArg())  {
-      S.Diag(getLocationOfByte(CS.getStart()),
-             diag::warn_printf_positional_arg_exceeds_data_args)
-        << (argIndex+1) << NumDataArgs
-        << getSpecifierRange(startSpecifier, specifierLen);
-    }
-    else {
-      S.Diag(getLocationOfByte(CS.getStart()),
-             diag::warn_printf_insufficient_data_args)
-        << getSpecifierRange(startSpecifier, specifierLen);
-    }
-
-    // Don't do any more checking.
+  if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex))
     return false;
-  }
 
   // Now type check the data expression that matches the
   // format specifier.
@@ -1714,22 +1729,8 @@ bool CheckScanfHandler::HandleScanfSpecifier(
   if (HasVAListArg)
     return true;
   
-  if (argIndex >= NumDataArgs) {
-    if (FS.usesPositionalArg())  {
-      S.Diag(getLocationOfByte(CS.getStart()),
-             diag::warn_printf_positional_arg_exceeds_data_args)
-      << (argIndex+1) << NumDataArgs
-      << getSpecifierRange(startSpecifier, specifierLen);
-    }
-    else {
-      S.Diag(getLocationOfByte(CS.getStart()),
-             diag::warn_printf_insufficient_data_args)
-      << getSpecifierRange(startSpecifier, specifierLen);
-    }
-    
-    // Don't do any more checking.
+  if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex))
     return false;
-  }
   
   // FIXME: Check that the argument type matches the format specifier.